To clarify
Its very difficult to obtain good links these days, generally they come as the result of creating good content, being a good brand and through a lot of hard work.
My suggestion would be to evaluate the sites you are dealing with, see what they are doing of interest to people, what they are doing which is different and try and exploit those areas. Promote that content through social channels, e-shots, good old fashioned word of mouth etc
Hopefully if the content is something that people find interesting, they will link to it, retweet and share it.
Admittedly, this is a simplistic overview but its the basis of what you should be doing.
If you are looking for further info, there is a ton of resource of Moz and other sites regarding content marketing, promoting content etc,
Hope that helps and good luck
Justin